NIO[SelectableChannel.register跟Selector.select会有锁等待冲突]

NIO[SelectableChannel.register和Selector.select会有锁等待冲突]

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结论： register得放在select之前进行Thread Dump信息：
"Poller-1" prio=6 tid=0x040f0400 nid=0x408 runnable [0x044df000]? ?java.lang.Thread.State: RUNNABLE? ? ? ? at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)? ? ? ? at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(WindowsSelectorImpl.java:295)? ? ? ? at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(WindowsSelectorImpl.java:277)? ? ? ? at sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:158)
? ? ? ? at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:87)? ? ? ? - locked <0x23b7df70> (a sun.nio.ch.Util$2)? ? ? ??- locked <0x23b7df60> (a java.util.Collections$UnmodifiableSet)? ? ? ? - locked <0x23b7dd40> (a sun.nio.ch.WindowsSelectorImpl)? ? ? ? at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98)? ? ? ? at com.zhh.nio.NioServer$Poller.run(NioServer.java:132)? ? ? ? at java.lang.Thread.run(Thread.java:722)
"Poller-0" prio=6 tid=0x040f0000 nid=0x14e4 runnable [0x0439f000]? ?java.lang.Thread.State: RUNNABLE? ? ? ? at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)? ? ? ? at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(WindowsSelectorImpl.java:295)? ? ? ? at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(WindowsSelectorImpl.java:277)? ? ? ? at sun.nio.ch.WindowsSelectorImpl.doSelect(WindowsSelectorImpl.java:158)
? ? ? ? at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:87)? ? ? ? - locked <0x23b77a98> (a sun.nio.ch.Util$2)? ? ? ? - locked <0x23b77a20> (a java.util.Collections$UnmodifiableSet)? ? ? ? - locked <0x23b76aa0> (a sun.nio.ch.WindowsSelectorImpl)? ? ? ? at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98)? ? ? ? at com.zhh.nio.NioServer$Poller.run(NioServer.java:132)? ? ? ? at java.lang.Thread.run(Thread.java:722)
"Acceptor" prio=6 tid=0x040ef800 nid=0x1250 waiting for monitor entry [0x03f1f000]? ?java.lang.Thread.State: BLOCKED (on object monitor)? ? ? ? at sun.nio.ch.SelectorImpl.register(SelectorImpl.java:133)? ? ? ? -?waiting to lock <0x23b7df60> (a java.util.Collections$UnmodifiableSet)
? ? ? ? at java.nio.channels.spi.AbstractSelectableChannel.register(AbstractSelectableChannel.java:207)? ? ? ? - locked <0x23b8da18> (a java.lang.Object)? ? ? ? at java.nio.channels.SelectableChannel.register(SelectableChannel.java:277)? ? ? ? at com.zhh.nio.NioSession.register(NioSession.java:50)? ? ? ? at com.zhh.nio.NioServer$Poller.register(NioServer.java:123)? ? ? ? at com.zhh.nio.NioServer.handleNewSession(NioServer.java:222)? ? ? ? at com.zhh.nio.NioServer$Acceptor.run(NioServer.java:236)? ? ? ? at java.lang.Thread.run(Thread.java:722)
Code层面：select：private int lockAndDoSelect(long timeout) throws IOException {? ? ? ? synchronized (this) {? ? ? ? ? ? if (!isOpen())? ? ? ? ? ? ? ? throw new ClosedSelectorException();? ? ? ? ? ??synchronized (publicKeys) {? ? ? ? ? ? ? ? synchronized (publicSelectedKeys) {? ? ? ? ? ? ? ? ? ? return doSelect(timeout);? ? ? ? ? ? ? ? }? ? ? ? ? ? }? ? ? ? }? ? }register：?protected final SelectionKey register(AbstractSelectableChannel ch,? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? int ops,? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Object attachment)? ? {? ? ? ? if (!(ch instanceof SelChImpl))? ? ? ? ? ? throw new IllegalSelectorException();? ? ? ? SelectionKeyImpl k = new SelectionKeyImpl((SelChImpl)ch, this);? ? ? ? k.attach(attachment);? ? ? ??synchronized (publicKeys) {? ? ? ? ? ? implRegister(k);? ? ? ? }? ? ? ? k.interestOps(ops);? ? ? ? return k;? ? }

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